my son has seasonal allergies and takes zertech on a daily basis. last week he was out of school for 4 days because of his allergies were so bad his face had swollen, his eyes had dark cricles and he was running a fever and had a very sore throat. i took him to the doc. she gave him a strep test and flu test both came back negative so she just refilled his zertech and sent us on our way. well it has been over a week and he cant quit couching. this morning I got him ready for school and he was coughing so hard he puked on his self 3 times. It was mostly mucus that came up so it has to be his allergies. I have been giving him cough medicine but its not helping. I cant send him to school cause hes coughing so much and keeps puking. I dont know what to do. he cant keep missing school. any advice would be awesome. thanks.